Proteoglycans are normal components of connective tissues and are believed to play an important role in the regulation and maintenance of the structural integrity of periodontal tissues. During periodontal disease a gradual dissolution of the connective tissue macromolecules takes place which may influence the concentration and composition of proteoglycans in these tissues. In order to understand the role of proteoglycans in healthy and diseased oral tissues the following important questions need to be answered: (1) which are the specific proteoglycans of oral tissues? (2) are these specific proteoglycans characteristic of various oral tissues? (3) How are these proteoglycans synthesized? We propose to seek answers to these questions through studies on structure and biosynthesis of proteoglycans of human gingival fibroblasts and of an established rat oral mucosal keratinocyte cell line. The cells will be incubated with radioactive sulfate, glucosamine or leucine and the labeled proteoglycans will be isolated and characterized. Monoclonal and polyclonal antibodies will be prepared against dermatan sulfate proteoglycans of soft connective tissues and heparan sulfate proteoglycans synthesized by keratinocytes. These antibodies will be utilized in the study of the biosynthesis of dermatan sulfate proteoglycans of human gingival fibroblasts and heparan sulfate proteoglycans synthesized by rat keratinocytes in culture. Pulse-chase label experiments in conjunction with immunoprecipitation will be carried out to determine the kinetics of the synthesis and processing of the proteoglycans and secretion of the completed proteoglycans into the extracellular matrix.